Animal Body Animal Body SystemsSystems

Objectives…(At the end of this lecture you should be able to):Objectives…(At the end of this lecture you should be able to):Summarize the functions of the digestive, respiratory, Summarize the functions of the digestive, respiratory, circulatory, nervous, skeletal and excretory systems.circulatory, nervous, skeletal and excretory systems.Compare a gastro vascular cavity with a one-way digestive Compare a gastro vascular cavity with a one-way digestive system.system.Differentiate open from closed circulatory systems.Differentiate open from closed circulatory systems.Distinguish asexual from sexual reproduction.Distinguish asexual from sexual reproduction.

Body Systems are specialized Body Systems are specialized to carry out different tasksto carry out different tasks

Simple animals like Simple animals like sponges carry out the sponges carry out the many tasks of living with many tasks of living with little specialization in the little specialization in the cells of their body.cells of their body.

More complex animals More complex animals have evolved tissues have evolved tissues and organs that are and organs that are specialized to perform specialized to perform specific functions.specific functions.

Body Systems are specialized Body Systems are specialized to carry out different tasksto carry out different tasks Seven important functions of these Seven important functions of these

tissues and organs are :tissues and organs are : DigestionDigestion RespirationRespiration CirculationCirculation Conduction of nerve impulsesConduction of nerve impulses SupportSupport ExcretionExcretion ReproductionReproduction

DigestionDigestion Purpose: Obtain energy & Purpose: Obtain energy &

nutrientsnutrients Sponges digest their food with Sponges digest their food with

their body cellstheir body cells Simple animals, such as Simple animals, such as

flatworms, have a gastro flatworms, have a gastro vascular cavity: a digestive vascular cavity: a digestive cavity with only one opening.cavity with only one opening.

More complex animals, like us, More complex animals, like us, have a digestive tract with two have a digestive tract with two openings: mouth and anus.openings: mouth and anus.

RespirationRespiration

Purpose: Exchange oxygen and Purpose: Exchange oxygen and carbon dioxide gasescarbon dioxide gases

Can only take place across a Can only take place across a moist surface.moist surface.

In simple animals like jellyfish In simple animals like jellyfish gasses are exchanged directly gasses are exchanged directly with their environment through with their environment through diffusion.diffusion.

More complex animals have More complex animals have specialized respiratory specialized respiratory structures like gills or lungs.structures like gills or lungs.

CirculationCirculation Purpose: Transport oxygen and Purpose: Transport oxygen and

nutrients to the other parts of the nutrients to the other parts of the bodybody

There are 2 types of circulatory There are 2 types of circulatory systems:systems: Open: heart pumps fluid containing Open: heart pumps fluid containing

oxygen through a series of vessels & oxygen through a series of vessels & is dumped into the body cavity.is dumped into the body cavity.

Closed: heart pumps blood through a Closed: heart pumps blood through a system of blood vessels. The blood system of blood vessels. The blood stays in the vessels the whole time.stays in the vessels the whole time.

CLOSED:

OPEN:

Conduction of Conduction of nerve impulsesnerve impulses

Purpose: Coordinate the Purpose: Coordinate the activities in an animal’s body activities in an animal’s body and allow animal to sense and allow animal to sense and respond to environment.and respond to environment.

Simple animals, like hydra, Simple animals, like hydra, have little coordination have little coordination among their nerve cells.among their nerve cells.

Complex animals, like Complex animals, like grasshoppers, have nerve grasshoppers, have nerve cords/ganglia & a brain.cords/ganglia & a brain.

Support: SkeletalSupport: Skeletal Purpose: Provide a framework Purpose: Provide a framework

that supports the body.that supports the body. Many soft-bodied invertebrates Many soft-bodied invertebrates

have a hydrostatic skeleton have a hydrostatic skeleton made of water like a filled water made of water like a filled water balloon.balloon.

Other invertebrates, such as Other invertebrates, such as insects & crabs, have an insects & crabs, have an exoskeleton: a rigid external exoskeleton: a rigid external skeleton.skeleton.

Complex animals, like dogs, Complex animals, like dogs, have an endoskeleton: hard have an endoskeleton: hard material such as bone embedded material such as bone embedded within the animal.within the animal.

ExcretionExcretion Purpose: Removal of Purpose: Removal of

wastes from cellular wastes from cellular metabolism (COmetabolism (CO22, ammonia, , ammonia, etc.)etc.)

Simple aquatic invertebrates Simple aquatic invertebrates & some fishes pass it & some fishes pass it through their skin/gills by through their skin/gills by diffusion.diffusion.

More complex animals have More complex animals have specialized excretory specialized excretory structures like kidneys.structures like kidneys.

ReproductionReproduction Purpose: produce offspring to Purpose: produce offspring to

ensure that the species ensure that the species survivessurvives

Two types of reproduction:Two types of reproduction: Asexual: does not involve fusion Asexual: does not involve fusion

of two gametes.of two gametes. EX: A sponge can reproduce by EX: A sponge can reproduce by

fragmenting its body. Sea fragmenting its body. Sea anemones pull apart into 2 anemones pull apart into 2 individualsindividuals

Sexual: a new individual is Sexual: a new individual is formed by the union of a male formed by the union of a male and female gamete.and female gamete. EX: egg + sperm = fertilization = EX: egg + sperm = fertilization =

blastulablastula

Is this sexual or asexualIs this sexual or asexual

reproductionreproduction??

Fun & Funky Fact: Fun & Funky Fact: Sea “horse” reproductionSea “horse” reproduction

Pregnant sea horse Pregnant sea horse fathers give birth.fathers give birth. A female sea horse A female sea horse

inserts her eggs into inserts her eggs into a pouch on the male’s a pouch on the male’s abdomen, where they abdomen, where they are fertilized. The are fertilized. The male incubates the male incubates the eggs until they are eggs until they are fully developed and fully developed and then gives birth to tiny then gives birth to tiny sea horses.sea horses.

FertilizationFertilization There are two types of There are two types of

fertilization:fertilization: External: occurs outside the bodyExternal: occurs outside the body

EX: Most aquatic animals simply EX: Most aquatic animals simply release the male and female gametes release the male and female gametes near one another in the water, where near one another in the water, where fertilization occurs…..think opening fertilization occurs…..think opening scene of Finding Nemo….they were scene of Finding Nemo….they were outside the mom.outside the mom.

Internal: occurs inside the females Internal: occurs inside the females bodybody EX: Animals that live on land don’t EX: Animals that live on land don’t

have water so the gametes would dry have water so the gametes would dry out. Internal fertilization allows it to out. Internal fertilization allows it to take place in a moist environment. take place in a moist environment.

Objectives…Objectives…(At the end of this lecture you should be able to):(At the end of this lecture you should be able to):

•Summarize the functions of the digestive, Summarize the functions of the digestive, respiratory, circulatory, nervous, skeletal and respiratory, circulatory, nervous, skeletal and excretory systems.excretory systems.

•Compare a gastro vascular cavity with a one-Compare a gastro vascular cavity with a one-way digestive system.way digestive system.

•Differentiate open from closed circulatory Differentiate open from closed circulatory systems.systems.

•Distinguish asexual from sexual reproduction.Distinguish asexual from sexual reproduction.

Quick TestQuick Test

Which two body systems in most Which two body systems in most animals are involved in taking up animals are involved in taking up oxygen from the environment and oxygen from the environment and transporting oxygen to body cells?transporting oxygen to body cells?

a)a) Digestive & RespiratoryDigestive & Respiratory

b)b) Respiratory & CirculatoryRespiratory & Circulatory

c)c) Circulatory & NervousCirculatory & Nervous

d)d) Nervous & ExcretoryNervous & Excretory

The correct answer is:The correct answer is:

BB